1. Field of the Invention
The present invention relates to an image stabilization control system directed to an electrophotographic process, and an image forming apparatus having a function thereof.
2. Description of the Related Art
With recent technical progress in an electrophotographic process, the electrophotographic process is becoming applied to printing of published matters with a comparatively small circulation and the like, instead of conventional offset printing and gravure printing. An image forming apparatus suitable for such published matters may be particularly called a production printer.
The production printer using an electrophotographic process is advantageous in that making a printing plate (plate making) is not necessary unlike offset printing or gravure printing, and printing can easily be done only by transmitting print data to the production printer.
On the other hand, a printed matter obtained by the production printer might be inferior in image quality to offset printing. Accordingly, there is a need to improve the production printer to have image quality of the same level as that achieved by an offset printing press. It is noted that image quality offered by the offset printing press needs to attain “chrominance of ΔE00≦1” in the case of evaluation using “chrominance” which is a deviation from a target color.
To manage such image quality and to further improve image quality (image reproducibility), an attempt has been made to evaluate a printed matter using color measuring means to optimize the electrophotographic process. An image forming apparatus disclosed in Japanese Laid-Open Patent Publication No. 2009-037138, for example, has a structure of creating a color separation table from color measuring means, such as a color sensor built in a printer body.
To achieve image quality of the same level as that of an offset printing press, it is necessary to evaluate factors of chrominance produced in a printed matter in more detail. In conventional methods, however, there is no technique known which, upon separating chrominance producing factors, adjusts the electrophotographic process based thereon.